Safety electric control contactor



Oct. 11, 1938. T. w. BARLOW- SAFETY ELECTRIC CONTROL CONTAQTOR I :Filed Jan 13, 1938 2 Sheets-Sheet 1 TAeoa ore Bar/enq- K BY A Pmnaa a. 11, was

2,l33,l 60 I NITED STATES PATENT OFFICE QONTACTOB Theodore W. Barlow, Detroit, Mich. I Application January 13, 1938, Serial No. 184,883

12 Claims.

This invention relates to electric control contactors. V

In various ones of the arts electric contactors are employed by which an operator or a plus rality of operators control the supply of power to a machine, power press, process, etc. Such contactors in'general are well known and are sometimes of the push button type.

In some cases it is desirable to prevent the unauthorized use of sucha contactor and to put it wholly out of use even against the wishes'of the operator, for example to prevent the accidental operation of a machine while it is being worked upon. ll In other cases it is desirable to insure or make necessary the use of the contactor or a plurality of like contactors, for example to insure that the hands of a machine operator ,or a plurality of operators are at the contactors and therefore out of danger of injury bythe machine during the operation thereof.

In other cases it is desirable to insure that such a contactor will remain permanently operated so that an operator therefor may optionally '25 be dispensed with.

It is also often desirable to prevent'the unauthorized tampering with or adjustment of such contactcrs. I

The present invention accomplishes the above described ends in a single structure. A contactor is provided having a handle or push button by which it may be operated; but may optionally be set to remain operated, or optionally set to remain inoperable independently of movement of the handle or push button- Preferably but not necessarily the contactor parts are enclosed within a casing or housing having a door or cover provided with a lock and key, the handle or push button being external to the casin and access to the contactor within the casing, as well as the setting of the contactor so that it may be operated, or so that it will remain inoperable, or so that it will remain operated, are underthe control of .the lock and key.

The primary object therefore of this invention is to provide a contactor by which any one of, or combination of, the above described functions and conditions of a contactor may be accom plished;

Another object 13m provide a contactor hav ing improved means bi which it may be converted into an'operable contaotonor a permanently operated contactor, or a permanently inoperable contactor, the object contemplating the effecting IQ of such conditions singly or in combination.

(OI. zoo-4 4) Another object of the invention is to provide a contactor in which the improved means referred to in the preceding paragraph is a rotary drum having a plurality of different positions in which the said changes to one or more of 5 the said conditions of the contactor may be effected in an improved manner.

Another object is to provide an improved contactor which may be converted from one condition to .another as described above, and locked w against unauthorized changes thereof in an improved manner.

Another object is to provide a contactor having means for converting it from one condition to another as described above and having locking 1 means for locking it against unauthorized change, and locking means also looking shut a contactorenclosing tamper-proof housing.

Another object is to provide an improved contactor which may be operatedto open or to close 20 an electric circuit by the turning of a lock by a' 'key, the contactor remaining locked in open or closed condition upon removal of the key.

Another objectis to provide an improved contactor controlling two electric circuits and nor- 5 mally maintaining one circuit closed, and the other open, and which may be operated to open the closed circuit and close the open circuit, and having means for optionally closing both circuits and maintaining them closed. 30

Other objects will be apparent to those skilled in the art to which my invention appertains.

' My invention is fully disclosed in the followinz description taken in connection with the accompanying drawings, in which: 35

Fig. 1 is a top plan view of an embodiment of my invention; V

Fig: 2 is a fragmentary front elevational view taken in the direction of the arrow 2 of Fig. 1;

Fig. 3 is a longitudinal sectional view of the 0 embodiment of .Fig. 1 taken approximately from the plane 3 of Fig. 1;

Fig. 4 is a view of the underside of a cover element and parts associatedtherewith of the embodiment of Figs. 1 and 3, the viewsbeing taken 5 approximately from the plane 4-4-4 of Fig. 3;

Fig. 5 is a top plan view of the embodiment of Figs. 1 and 3 with the said cover element of Fig. 4 removed and with the wall of a housing element thereof shown in section;

Fig. 6 is a fragmentary sectional view taken from the plane H of Fig. 3, and the view may also be considered as taken from the plane 6-4 of Fla. 5;

m. '1 is'a fragmentary view of a part of m. u-

taken from the plane 1-1 of Fig. 8;

Fig. 8 is a fragmentary view'similar to part of Fig. 5, with operative parts thereof in different positions and in the same position as the parts upon and eonnectedto a rotary element 1 of a lock of Fi 7 Fig. 9 isa fragmentary view similar to Fig.1

with the operative parts thereof in still another.

position Fig. 10 is a fragmentary sectional view taken fromthe plane ill-Ill of Fig. 3.'

Fig. 11 is-a view of an operative part shown in Fig. 5, but illustratinga modification thereof and illustrating in more detail a lock device which I may employ.

Referring to the drawings, I have shown at I a housing inthe form of an upwardly fopen box, and at 2 a cover for the box and forming, in association therewith, 'a substantially closed housing. The cover 2 may. be secured to the box I by screws 2-2 in a well known manner, the screws beingprojected through perforations 4-4 in the cover and threaded into suitable corner bosses in the upper portion of the box I, not completely shown to avoid complication in the drawings.

A rotary barrel 5, which performs a number-of functions to be described, is mounted transversely of the box l'adjacent to one end thereof. One end of the barrel 5 rotates upon a trunnion 6 securedupon the adjacent side wall of the box i and the opposite end of the barrel is supported *8 of the lock 8 to turn the lock part 1 and the key thus constitutes the only means by which the barrel maybe rotated, the barrel .I being locked by the lock against rotation when the key is withdrawn. It is believed unnecessary to illustrate the inner part of such a lock, the same being well known. Thebarrel may be secured to the lock part 1 in any suitable manner, one means being a spring l0, Figs. 5 and 6, which holds the barrel toward-the-lock and maintains a sleeve ll of the barrel in telescopic relation with the lock part 1, as at l2, the sleeve and lock part being formed so as to be non-rotatable relatively.

The cover 2 has secured'on 'its'under side a plate It having a large opening I in the central part thereof. The plate It is riveted by rivets Ii-li to the under side of the cover 2 and a diaphragm it of flexible material such as leather is disposed between the plate It and the cover 2, before it is riveted thereto, so that when the cover 2 is secured upon the box I by the screws, 2-2 as described, the diaphragm will seal all of the parts within the box and under the diaphragm.

The plate I! has depending therefrom laterally spaced ears l1-l1, through aligned perforations in which a transverse bearing pin II is disposed. A sheet metal contactor-actuator II is mounted to hingingly move on the pin ll. 11 M 18 rearward portion thereof ears 20-22 bent upwardly therefrom and provided with aligned perforations through which the pin II is projected. A push button support 2i is also 'hingingly mounted upon the pin II, the support 2| being disposed above the pin it and having depending ears 22-22 thereon through aligned perforations in which the pin II is projected. A. spring 22 is wound around the pin it and one end 24 thereof To turn theper side of the actuator l9 tendingto move them apart. a I

The support 2! has a pair of depending hooks 26-26 the lower ends of which are bent inwardly under the actuator i9 in forward portions thereof, so that the movement apart of the actuator l9 and the support 2| is limited and stopped by the hooks 26. By this means they are free tohingingly move toward each other by the yielding of the spring 23, or may hingingly move in unison; with the actuator I9 in engagement with the hooks 26-26, for purposes to be described.

Means is provided tolock the cover 2 on the box I, under control of the look even if the screws I3-i2 have been removed. To thisend the ears l1-l1 on the plate i3 have notches 21-21 formed therein under an inwardly flange 28 on the rearward end wall of the box I;

' tion of the cover before it has moved sufliciently to remove the'notches 21-21 from under the flange 28 referred to, so that before the cover 2 can be removed the forward end portion thereof must be raised suflioently to-permit the hook 28 to be moved forward over the top of the flange 3 I, and it follows that if the forward portion of the cover be held downwardly the hook 29 cannot be so raised and the cover cannot be removed. To thus prevent theforward end of the cover from "being raised, a hook 22, integral with the plate l2, Figs. 3, 4 and. 6, depends therefrom, the lower end of the hook 32 hooking under-a flange 33 on the end of the barrel 5 adjacent its bearing trunnion 6. In order at will to remove the cover 2 to give cess to parts to be described within the box I, the key must be inserted in the lock and the lock turned, turning the bar'rel.5 through 180 from v the operativeposition illustrated. This will rotate a recess 24 in the flange 33 until it comes opposite the'hook 22,- and then the forward end of the cover 2 may be raised, the hook passing upwardly through the recess 34 and when the hook 22, above referred to, has thereby been raised sufficiently to ride over the flange ii of the box, the cover may be moved forwardly to remove the notches 21-21 from under the flange 28, and then the cover may be removed. 7 Thus one of the functions of the lock 8 and the barrel 5 is to lock the'cover on the box to prevent unauthorized removal thereof and tampering withthe parts within the box to be described, including the barrel itself.

Secured to the upper side of the supp rt 2| is the cylindrical stem 35, a push button 36, the stem projecting inwardly through the cover 2 through a relatively large perforation 31 therein, the push button 26 being of large diameter, suitable to be operated to push it downwardlypy a blow or bypressure from the handor palmof the operator. The stem 35 clamps the diaphragm' it between it and the support 2 and may have a portion of reduced diameter 28 projected through perforations inthe diaphragm and in the support and riveted over on the underside of the support. By this ar- I rangement the diaphragm prevents the entrance I I s,1ss,1eo ofdust or foreign 4 tion 31 tothepartsilnderthediaphragm.

If; however, for reasons to-be described the ,actu-j ator i9 1 is prevented" from moving downwardly the support '2l move downwardly against the tension of the'sp'ring 23 as described without transmitting the blovFor ,pressurewhich may have been given to the pushbutton a tothe actuator is with the possibility of it and parts associatedtherewith; and in any case-,-;the

stopped and the blow given thereto absorbed by the striking of the lower face 33 of the push button upon the .upper side-of the cover 2. Thus u matter how violently thepush-button is l w it cannot injure parts within the housing. 7

when the barrel si mtneposition mustratedfl inFigsx3and5Ya recess 44 on the barrel is disposed directly under the book 23 so thatwhen the push button 34 is depressed, the contactor actuator is will be depressed, being moved downwardly by the tension of the spring 23 with a predetermined amount of cushioned force, the hook in its lower position being indicated in broken lines at 4i, and this downward movement of the which will now be described.

' tacts 42 and 84.

A contactor base 42 of insulating material is secured upon the bottom of the box by screws 43-4l, Fig. 5. Preferably integral with the base 42 are upstanding laterally spaced-sides 44-44 through which a shaft 43 extends. Upon this shaft is oscillatably supported a contact carrier 46, Figs. 3 and 5, having rotatably mounted thereon a roller 41 maintained in contactwiththe un-v derside of the intermediate portion of' the actuator l9, as shown in Fig. 3, by yieldable resilient,

means tending to rotate the contact carrier 46. clockwise, as viewed in Fig. 3. The resilient means preferably comprises a pair of springs 48-43 wound around trunnions 4s 4s projecting laterally from opposite sides of the carrier 46 and through which the shaft 4| extends, one 7 end 50 of each spring being lodged one. shoulder 5| onthe carrier and the other end 52 being lodged against a shoulder, I3 on the adjacent one of the sides 44.

The contact carrier has a pair of longitudinally spaced depending arms 44 and SI each of which carries a contact bridging bar I! and 51, the preferred mounting for the bar being shown for the bar 56, in Fig. 10, wherein a pin 53 is secured in the arm projecting inwardly therefrom; the pin is telescoped through a perforation inthe'bar 56, and a spring I! abuts at one end upon the head 60 of the pin and at the other end upon the bar, resiliently holding the bar against the arm 54, but permitting the bar to yield toward the pin head when the arm 44 moves to engage contacts ii and 32 on the bar with stationary con- 3 and 5 are mounted on metal pieces 34 and 04 on the base 42 and terminal nuts 31 and II are provided for making electrical connection there- -nected to theterminal The contacts 43 and 44-, Figs.

'tactorwillresulh'.

, Circuit wires-11, n, n, u are shown' connuts respectively, 61, 38, "and". r I

- As will now be apparent, a circuit connected toIthe wires II and 30 will normally be closed through the engaged contacts II and II and ill counter-clockwise, as viewed in Fig. 3, and disengage the said contacts opening the said circuit and by engaging the contacts "-43 and 4244 will close the circuit of the wires I1 and I3.

' *Thus another function of the barrel 5 is pro- I g n v a vided'f'namely, topermit the closing of a circuit downward movement of the push button was 1%,111P1. and'the-opening of'a circuit "40, by

, op ration of the push button 30. Obviously, if

one oftlre'bars 54 or 51 be omitted, then the only I operation would be to close the circuit IL-ll or to open the circuit 13-14 when the push button is operated.

Afterthe contactor has been operated as above described by rocking the carrier 44 counterclockwise, as viewed in Fig. 3, it may belocked so that it will remain in that position. To accomplish this, the push button 36 is depressed to operate the contactor which places the hook 29 is therefore another function of the drum to lock the contactor in operated position.

Still another function of the drum will now be described. In some cases it may be desired, in eifect,to eliminate entirely the functions of the device, that is to say, to close both circuits 'i'I-il and 19-40, and to lock them closed. To this end prises a metal bar 32, embedded in the material of the barrel 5 and having end portions 34 and 34 projecting laterally therefrom; and a pair of spring-type contacts and 36 are connected to the metal pieces I3 and "on the base 4i and normally, resiliently pressed against the side of the barrel 5, and the spring contacts and bar end portions 33 and 34 are so disposed that when the barrel is rocked into the said locked position,

the spring contacts engage the bar and complete an electric circuit therethrough.

- Another function of the barrel 5 is to prevent any operation of the device and to lock it in such condition, and to this end the barrel 8 is provided with a solid portion I1 which, by inserting the key and rotating the lock and the barrel, may be brought directly under the hook 20, as shown in Fig. 9.

By this means, when the push button I. is depressed, the .push button support will be depressed and the push button 34 will be stopped upon the top of the cover2, but the actuator I! willbe held up and no The walls of the box I, for example the end walls thereof Fig. 3, may be provided with perforations as thoseshown at and 80 through operation of the conbox wall.

which electric-wires may be conducted to the terminals. Such outlets may be of usual, or any sacrificing its advantages and within the scope of centrically located pin 91 thereon projecting into a recess 98 in the barrel to turn the barrel when the plug is rotated. A leather or like sealing washer 93 is disposed between the inner end of the shell and the bottom of a recess H30 in the barrel. The spring to effects pressure engagement between the washer and'recess bottom and shell end. In the modification illustrated in this figure, a coaxial trunnion'lfll is formed on the barrel and projects into a recess or bore H02 in the box wall.

From the foregoing it will now be clear that I i have provided a contactor device, comprising a contactor operating element or handle, which in the preferred form is a push button; and have arranged a contactor which can be operated thereby; and have provided a lock mechanism' by which thecontactor can be operated by the push button; can be rendered inoperative thereby, or can be operated and locked in operated position; and I have provided means also by which the operative parts are entirely enclosed in 'a dust and dirt proof enclosure or housing Which may be locked closed to prevent unauthorized access thereto; and while all of these functions arecombined in a single device, it will be apparent that any one or any combination thereof may be provided and utilized optionally.

The four portions of the drum above described are indicated upon a dial 9!, associated with the lock 8, by the following legends: Use. when the key is turned to that position, indicates that the contactor may be operated by the push button; Off indicates the position in which the contactor cannot be operated; n indicates that the contactor has been operated and locked in that condition; and Open indicates that the drum is in position to permit the cover. to be removed.

In some cases it may be desired to utilize the device above described merely to close or open a circuit, such as that comprising the wires I5 and I6, and to leave. the circuit locked in closed or open position. To that end the push button 36, and actuator I9 and carrier 46 may beomitted.

,Then when the key is inserted in the lock it may withdrawn the barrel being locked in position' will maintain thesaid circuit condition against unauthorized change. I

The barrel 5 when utilized in this manner as well as in the more comprehensive'manner dey scribed above is in ecect a selector element and may have other forms than the barrel form illustrated herein. In this respect and in other' respects as well my invention is not limited to the exact details of construction illustrated and described. Changes andfmodifications may be made, within the spirit of my invention without the. appended claims.

I claim: 1. In an electric contactor construction, a main .frame, two sets of contacts on the frame, an

prevent movement thereof and corresponding oscillatory movement .of the carrier thereby, and

in another position permits movement of :the-

contactor'operating element, lock means assoclated with the contactor operating element and the barrel engageable in another rotative position of "the barrel, to lock the contactor operating element in carrier oscillated position, a cover for the contactor, locking means on the cover and barrel engaged to lock the cover on the frame in all three said rotative positions, and disengageable to unlock it upon rotation of the barrel to a fourth position.

2; In an electric contactor construction, a

housing, a push button external to the housinghaving a stem projecting into the housing, a reciprocable member in the housing .normally reciprocated in one directios by spring means and reciprocable in the other direction by the push button stern, contact'means carried by the reciprocable member, a first and a second pair of 'contacts in the housing, the first pair being normally' bridged by the contact means and upon reciprocation of the reciprocable member by the push button stem the first pair being unbridged and the second pair being bridged, means comprising an element manually movable from outside the housing to hold the second pair bridged independently of the push button stem and auxilary contact means operated by movement of the manually movable element to effect bridging of the first pair of contacts.

3. In an electric contactor construction, a housing, a push button external to the housing having a stem projecting into the housing, a reciprocable member in the housing normally reciprocated in .one direction by spring means and reciprocable in the other direction by the push button stem, contact means carried by the reciprocable member, a first and a second pair of contacts in the housing the first pair being normally bridged by the contact means and upon reciprocation of the reciprocable member by the push button stem the first pair being 'unbridged and the second pair being bridged, a rotary element extending into the housing and rotatable from outside the housing, means associated with the rotatable element and the reciprocable member by which when the reciprocable member has been reciprocated by the push button stem to bridge the second con- 1 tacts the rotary member may be rotated to a posl-,

tion in which it holds the reci'procable member reclprocated independently of the push button stem, and auxiliary contact means associated with the-rotary element and operated by said rotary movement thereof to bridge said first pair of contacts.

4. In an electric contactor construction, a housing, a push button external to the housing having a stemyprojecting into the housing, a

sin-ins retracted arm pivoted in the housing and movable by the stem, an osciliatable element supported in the housing and retracted in one oscillatory direc- ,ing latch means on the barrel and arm by which upon rotating the barrel to a predetermined position the arm and oscillatable element may be latchedin a position in which the second pair of contacts'is bridged and the firs't'pair unbridged, and auxiliary contacts on the barrel and housing engageable upon said rotation of the barrel to said position to brid e the first pair of contacts.

5. In an electric contactor constructioma housing, a push button external to the housing having a stem projecting into the housing, a spring retracted arm pivotedin the housing and movable by. the stem, an oscillatable' element supported in the housing and retracted inone oscillatory direction by spring means and movable in the other direction by the arm, and carrying bridg-' ing contacts, a first and a second pair of contacts in the housing alternately bridged by the bridging contacts upon oscillatory movement of the oscillatable element, the first pair being normally bridged, a rotary barrel in the housing manually rotatable from outside the housing, interengaging abutment means on the barrel and arm by which upon rotation of the barrel to a predetermined position the arm is prevented from being moved by the push button stem.

6. In an electric contactor construction, a housing, a push button external to. the housing having astem proiectinginto the housing, a reciprocable member in the housing normally reciprocated in I one direction by spring means and reciprocable in the other direction by the push button stem, contact means carried by the reciprocable member, a first and a. second pair of contacts in the housingthe first pair being normally bridged by .the contact means and upon reciprocation of the reciprocable-member in said other direction by the push button stem, the first pair being unbridged and the second pair being bridged, manuing means to bridge the'fir'st and second pairs of contacts respectively when reciprocated, auxiliary bridging means manually movable to bridge the first contact pair. a lock comprising a lockbarrel normally locked to the frame against rotation and releasable by a key and when released being manually rotatable, means associated with the barrel rendered efi'ective by rotation of the barrel to hold the reciprocable member in the reciprocated'direction' to bridge the second pair Y of contacts and to also hold the auxiliary bridging means in position to bridge the first pair of contacts.

8. In an electric contactor construction, a

mainsupportingframeafirstandasecond pair of contacts, a reciprocable member reciprocable in one direction by spring means and in the other direction by a handle and carrying contact bridgingmeanstobridgethefirstandsecondpairs of contacts respectively when reciprocated, auxiliary bridging means manually movable to bridge the first contact pair, a lock comprising a lockbarrel normally locked to the frame against rotation and releasable by a key and when released being manually rotatable, means associated with the barrel operated by rotation of the barrel to hold the reciprocable member in the reciprocated direction to bridge the second pair of contacts and to also hold the auxiliary bridging means in position to bridge the first pair of contacts.

9. In an electric contactor construction. a main frame, a first and a second pair of contacts, a reciprocable member reciprocable in one direction by spring means and in the other direction by a handle and carrying contact bridging means to bridge the first and second pairs of contacts respectively when reciprocated, auxiliary bridging means manually movable to bridge the first contact pair, a lock comprising a lock-barrel normally locked to the frame against rotation and releasable by a key and when released being manually rotatable, means associated with the barrel rendered effective by rotation of the barrel to one position to hold the reciprocable member in'the reciprocated direction to bridge the second pair of contacts and other means associated with the barrel and renderedeifective by rotation of the barrel to another position to prevent reciprocation of the reciprocable member.

10. In an electric contactor construction. a housing, a cover closing the housing, a first and a second pair of contacts in the housing, a reciprocable member in the housing reciprocable in one direction by spring means and in the other direction by a handle exterior to'the housing and carrying contact bridging means to bridge the first and second pair of contacts respectively when reciprocated, auxiliary bridging means manually movable to bridge the first contact pair, a lock comprising a lock-barrel normally locked to the frame against rotation and releasable by a key and when released being manually rotatable, means associated with the barrel rendered efiective by rotation of the barrel to a predetermined position to hold the reciprocable member in the reciprocated direction to bridge the second pair of contacts and latch means associated with the barrel and operated by rotation of the barrel and effective in said predetermined pomtion thereof to latch the cover on the housing.

11. In an electric contactor construction, a housing, a cover closing the housing, a push button external to the housing having a stem projecting into the housing, a reciprocable member in the housing normally reciprocated in one direction by spring means and reciprocable in the other direction by the push button stem, contact means carried by the reciprocable member, a first and a second pair of contacts in the housing, the

first pair being normally bridged by the contact means and upon reciprocation of the reciprocable member by the push. button stem the first pair being unbridged and the second pair being bridged, means comprising an element manually movable from outside the housing to a position to hold the second pair bridged, auxiliary contact means operated by movement of the manually movable element to said position to effect bridging of the first pair of contacts and latch bridged by the contact means and upon reciprocation of the reciprocable member by the push button stem, the first pair being unbridged and the second pair being bridged, means comprising an element manually movable from outside the housing to hold the second pair bridged in one position of the movable element and auxiliary contact means operated by movement of the manually movable element to said position to effect bridging of the first pair of contacts and means rendered efiective by movement of the manually movable element to another position to prevent reciprocatory movement or the'reciprccable element. 

